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Betaine improves sprint cycling performance

Posted on Wednesday, 4 April, 2012 by anthony

Research reported in the Journal of the International Society of Sports Nutrition found that supplementation with Betaine (Trimethylglycine), at a dose of 2.5g/daily for 7-days significantly improved cycling sprint performance (Pryor et al., 2012).

What is Betaine (trimethylglycine)?

Betaine (or Trimethylglycine) is an important nutrient found in a variety of foods (whole grains, spinach, sea food etc). It is an organic osmolyte that is known to possess osmoprotective properties - it protects cells during periods of physical stress stress, such as dehydration or heat stress. Betaine is also known to be a methyl donor – the process of transferring a methyl group (CH3) is called methylation and is known to be important for a number of biochemical processes including the synthesis of neurotransmitters, metabolism of lipids, DNA, and cellular reproduction. Betaine appears to be beneficial for liver, heart, and kidney health as well as for lowering homocysteine levels.

The betaine research

The researchers compared the effects of a carbohydrate electrolyte drink containing 2.5g of betaine with a placebo (the same drink without betaine). Subjects (sixteen college age males and females) completed an initial sprint cycling test for baseline test figures and were then assigned to either placebo or betaine groups – subjects were unaware of which group they were assigned to – and instructed to consume half of their drink twice daily for a seven day period followed by a second cycling sprint test. All subjects then had a three week washout period before consuming the opposite drink for seven days and completing a third cycling sprint test. The sprint tests consisted of four 12 second maximum work bouts (resistance was set to 5.5% of body weight during sprints) separated by 2 ½ minutes cycling with no resistance.

The results

Supplementation with betaine was found to significantly increase sprint cylcling performance compared with baseline figures (5.5 ± 0.8% increase compared with baseline) and compared with the placebo drink (3.5 ± 0.2% increase compared with placebo). The researchers suggest that the increase in cycling sprint performance may be due to betaine supplementation increasing stores of muscle creatine, enhancing muscle growth, or through the protection of muscle cells from stress-induced damage.


Pryor J L, Craig S A S, and Swensen T. (2012) Effect of betaine supplementation on cycling sprint performance. Journal of the International Society of Sports Nutrition 2012, 9:12 doi:10.1186/1550-2783-9-12.

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